What's the c342d code Chevy silverado?

When You have a check engine light on in Your Chevy Silverado the first thing that You should do is stop driving as soon as possible. It can be dangerous to drive with a check engine light on because it can cause more damage to Your vehicle. The next thing You should do is use an OBD II scan tool when You have stopped driving to see the code that is stored in Your truck's ECU. If You have a C342D code then that means that there is either a problem with the throttle position sensor or the idle air control valve. If Your engine is running rough and stalling that usually means there's a valve problem. If You find the vehicle is running rich then that is usually a sensor problem.